The pace at which scientists are developing new energy sources for portable electronics is dramatically speeding up as the industry races to make smaller devices with longer-lasting batteries.

Canadian government researchers at the Alberta Research Council (ARC) announced this week that they have built a working prototype of a fuel cell that uses hydrogen gas as a fuel but can be adapted to run on a variety of sources such as natural gas, butane or propane.

Meanwhile, a team from Cornell University last month unveiled a device that converts the energy stored in radioactive material directly into mechanical motion, which in turn moves the parts of a miniscule machine to generate electricity.